A Common-Sense Guide to Data Structures and Algorithms, Second Edition, 2nd Edition

Recursive Category: Repeatedly Execute

Over the course of tackling various recursive problems, I began to find that there are various “categories” of problems. Once I learned an effective technique for a certain category, when I found another problem that belonged to the same category, I was able to apply the same technique to solve it.

The category that I found to be the easiest was one in which the goal of the algorithm was to repeatedly execute a task.

The NASA spacecraft countdown algorithm from the previous chapter is a great example of this. The code prints a number such as 10, and then 9, then 8, all the way down to 0. While the number the function prints is different each time, we boil down the code’s essence to the fact that it is repeatedly ...